Sun tanning describes a darkening of the skin (especially of fair-skinned individuals) in a natural physiological response stimulated by exposure to ultraviolet (UV) radiation from sunshine or from artificial sources such as a tanning bed. With excessive exposure to ultraviolet, a sunburn can develop. Cause and effect

Two different mechanisms contribute to the UV-induced darkening of the skin. Firstly the UVA-radiation generates oxidative stress which in turn oxidises pre-existing melanin. This leads to rapid darkening of already existing melanin. The second mechanism is the increased production of melanin (melanogenesis).[1] It is a reaction of the body to photodamage from UVB.[2] This melanogenesis is triggered by the same DNA damage that causes sunburn. Melanogenesis leads to delayed tanning. It first becomes visible about 72 hours after exposure.[1] The tan that is created by an increased melanogenesis lasts much longer than the one that is caused by oxidation of existing melanin.

Darkening of the skin is caused by an increased release of the pigment melanin into the skin's cells after exposure to ultraviolet radiation. Melanin is produced by cells called melanocytes and protects the body from direct and indirect DNA damage absorbing an excess of solar radiation, which can be harmful. Depending on genetics, some people can darken quickly and deeply whereas others do not darken much at all.

The ultraviolet frequencies responsible for tanning are often divided into the UVA (315 to 400nm wavelength) and UVB (280 to 315nm wavelength) ranges.

UVB

triggers the formation of CPD-DNA damage (direct DNA damage) which in turn induces an increased melanin production[2] is more likely to cause a sunburn than UVA as a result of overexposure. The mechanism for sunburn and increased melanogenesis is identical.[3] Both are caused by the direct DNA damage (formation of CPDs) reduced by virtually all sunscreens in accordance with their SPF is thought to cause the formation of moles and some types of skin cancer (but not melanoma) causes skin aging (but at a far slower rate than UVA.)

produces Vitamin D in human skin
UVA

causes release of preexisting melanin from the melanocytes causes the melanin to combine with oxygen (oxidize), which creates the actual tan color in the skin seems to cause cancer less than UVB, but causes melanoma, a far more dangerous type of skin cancer than other types is blocked less than UVB by many sunscreens but is blocked to some degree by clothing is present more uniformly throughout the day, and throughout the seasons than UVB

[edit] Health benefitsThe skin produces vitamin D in response to sun exposure (in particular, UVB waves in the 285nm to 287nm range), which can be a health benefit for those with vitamin D deficiency. In 2002, Dr. William B. Grant published an article claiming that 23,800 premature deaths occur in the US annually from cancer due to insufficient UVB exposures (apparently via vitamin D deficiency).[4] This is higher than 8,800 deaths occurred from melanoma or squamous cell carcinoma. This does not mean that sun tanning is categorically safe or beneficial. Spending several minutes in the sun is long enough to obtain your daily dose of vitamin D. Another research[5][6] estimates that 50,000–63,000 individuals in the United States and 19,000 - 25,000 in the UK die prematurely from cancer annually due to insufficient vitamin D.

Another effect of vitamin D deficiency is osteomalacia, which can result in bone pain, difficulty in weight bearing and sometimes fractures. This work has been updated in Grant et al. 2005[7] and Grant and Garland, 2006[8] In addition, it was reported that in Spain, risk of non-melanoma skin cancer is balanced by reduced risk of 16 types of cancer [Grant, 2006][9]

According to research conducted in 2007 by Cozen, Gauderman, Islam, and Mack [10] [11], sun exposure during childhood prevents multiple sclerosis later in life....

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Tanning is a dangerous activity and though many people know why, they continue to partake in the activity. Tanning is dangerous because it requires the body to receive an overexposed amount of ultra violet radiation (Addicted to the Tan.) Even though tanning has faded in and out throughout the years, tanning is a popular activity among this generation. The effects of tanning are not only harmful, they are deadly as well.
Most people think if tanning as an activity that only occurs during the summertime or at the beach. But Trisha Paytas, a model working in Los Angeles, feels that she needs a tan to be comfortable in her own skin. Trisha has not missed a day of tanning in over ten years, which means that her skin is at an extremely high risk for damage. After she is finished tanning, Trisha gets a spray tan to make sure her skin tones are blended evenly all over her body. Trisha states that, “If you told me that I have skin cancer, I don’t think I would stop; scrape it off and keep going.” Trisha Paytas is completely aware that she is putting her body at risk by tanning, but she refuses to stop (Extreme Tanner Says Skin Cancer Wouldn’t Stop Her).
People believe that being tan is a type of protection from receiving sunburn or other skin damage, although this is entirely untrue. Tanning actually increases the risk of developing...

... The effects of sun exposure on the human body. |
shanatorres
11/23/2012
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Every hour at least one American will die of skin cancer caused by exposure to the sun. These statistics are alarming and most people are unaware that the sunshine that we all love so much is in fact a threat to our health and good looks. It is up to us to educate ourselves and our children on the harmful effects of sun exposure on the human body like premature aging, physical damage to the body, and cancerous diseases.
Premature aging is one main effect of sun exposure. Becoming an old looking, wrinkly person is the last thing people look forward to, but did you know that the average person gets eighty percent of their lifetime exposure to the sun by the time they are eighteen. Most people would agree that seldom do parents apply sun screen to their children’s skin before going swimming or to the beach and almost never reapplying it as necessary. No child grows up worrying about putting sun screen on themselves before going outside to play, so why do people seem so shocked when they begin to age prematurely? Fine lines and wrinkles begin to appear on the face, chest, neck, and hands first, because those are the places on our body that are exposed to sun light most often. Ultraviolet rays from the sun, damage the elastin fibers in our skin and this...

...outer canvas. Teenagers, even adults, craving the desire of having sun kissed skin year round. Skin so smooth and radiant making a person feel so empowered about their appearance. To some, tanned skin is a confidence booster but to others it’s just the way of life; a daily ritual of bronzing the body in a local tanning bed. The tanning epidemic in females has increased throughout the years to present the perfect image to their peers. Young teenagers are tanning on a daily basis using up their monthly tanning packages before their prom. Models tanning weekly to keep up with the summer tan look for swimsuit photo shoots that are shot in the winter months. Indulging in tanning for a brief 15 minute session is relaxing and unwinds the busy day. Unknowingly, the calming tanning bed is dangerous deep down. Tanning is harmful to the body is many different ways. The underlying effects of tanning aren’t so obvious to the person lying or standing a few inches away from the UV rays in the nearby tanning salon. The almost instant gratification a tanning bed provides in a single session is more convenient for those who wish to get the golden brown tan because the availability of a bronzing tanning lotion combined with UV rays is a great benefit to the customer as it helps enhances the tanning...

...﻿SUN BEDS VS SUNBATHING VS FAKE TANS
There are lots ways of getting a beautiful glowing tan that make you feel good and look good not only in summer but all year round but there are also dangers of getting this healthy tanned look.
Sun beds.
Lots of sun beds are coin operated these days with no supervision these can be found in every city on nearly every high street, there is nothing or no one telling you or allowing you are only to use them for a limited amount of time and certainly no one stopping teenagers from using them as often as they like and for as long as they like. They do provide machines for you to purchase goggles, the only piece of safety equipment they expect you to use, but only if you want to the choice is up to you. Sun screen protection is not used on sunbeds.
Experts have found that on average some sun beds in England emit harmful radiation that is more than twice as high as the recommended safe level.
Sun beds are twice as likely to cause cancer.
Even in so short a time as a 10 minute session maybe twice a week is more likely to cause skin cancer than spending time in the heat of the sun between the hours of midday and 3 in the Mediterranean.
Over a 100 deaths a year and over 370 reported new cases of malignant skin cancer are caused by the use of sun beds.
Cancer research UK has lobbied parliament along with the help of people...

...Tori Cash Cash 1
Senior Project
Mrs. Nist
The Dangers of TanningSuntanning or simply tanning is the process where by skin cancer is darkened or tanned. The process is most often a result of exposure to ultraviolet (UV) radiation from the sun or from artificial sources, such as a tanning bed, but can also be a result of windburn or reflected light. Many people deliberately tan their skin by exposure to the sun, called sun bathing, or by the use of artificial tanning methods. Some people use chemical products which can produce a tanning result without exposure to ultraviolet radiation.
The sun's rays contain two types of ultraviolet radiation that reach your skin: UVA and UVB. UVB radiation burns the upper layers of skin (the epidermis), causing sunburns.
UVA radiation is what makes people tan. UVA rays penetrate to the lower layers of the epidermis, where they trigger cells called melanocytes to produce melanin. Melanin is the brown pigment that causes tanning.
Melanin is the body's way of protecting skin from burning. Darker-skinned people tan more deeply than lighter-skinned people because their melanocytes produce more...

...2014
What are the effects of tanning beds?
Meet Natalie. She started tanning when she was 16 years old because she was convinced it made her feel prettier. During her college years, she would go once every 2 weeks and then began going once a week. She always joked about how she would get skin cancer, but thought it would never happen to her. When she was 21, her doctor noticed a spot on her back, which turned out to be melanoma; she went through many surgeries to remove cancerous skin. Now she is left with multiple scars and compares herself to looking like Frankenstein with all her scars. According to “Research Sheds Light on Indoor Tanning and Cancer Risk.” Journal of the National Cancer, ‘”People who use indoor tanning have a 15% higher rate of having basal cells and 11% higher chance of having melanoma compared to those who are not exposed to the tanning UV light” There are safer options for tanning that are worth trying. I know way too many people whose lives have been changed by the use of tanning beds, which is what sparked my interest in this subject.
Many of my friends and some of my family use the tanning bed as a confidence booster for feeling pretty rather than pale, but I wish they could understand that they are paying a large price for beauty. “People tanning before the age of 30 are 70% are more likely to develop melanoma” (Watson)....

...According to the Skin Cancer Foundation, on an average day, nearly thirty million people tan indoors in the United States (“Skin Cancer Facts” 2011). What is even more alarming is, “a new study has shown that people who use tanning parlors once a month or more have an increased risk of developing malignant melanoma by 55%. Melanoma is one of the deadliest forms of skin cancer” (“Skin Cancer Facts” 2011). If this statistic does not scare those who use tanning beds, it should. Although a nice bronze glow accompanies your body after your trip to the tanning bed, a lifetime of trouble for your skin will follow, also. Is a nice tan really worth a lifetime of health concerns for your skin? To many, it is because of societies definition of beauty. Society thinks the idea of beauty involves harming their skin and receiving potential cancer in return for laying in a bed for “color”. This needs to change just as much as we need to stop the increase of skin cancer. One-way to stop this delusional sense of beauty and to decrease the number of skin cancer patients is to ban tanning beds. Tanning beds should be banned in the U.S. because although you may get instant, temporary, tan skin, developing a deathly cancer called melanoma can create more permanent unpleasant medical issues and the real idea of beauty needs to be re-established.
To begin, many people have heard the term melanoma but it is...

...6 August 2013
Tanning Beds Should be Banned for Minors Who Are Under the Age of Eighteen.
Tanning is a growing trend nowadays in America “despite increased public awareness of the link between skin cancer and ultraviolet radiation (UV) from both sun and tanning beds”(Kourosh). Despite the effort to educate the public and limit young people’s access to indoor tanning facilities, indoor tanning has not significantly decreased (Kourosh). Dear Rep. Holy, as a representative of Washington State, you should consider regulations that forbid people under the age of 18 using tanning beds.
Experts have long agreed that there is no such thing as a good tan and tanning beds are even more dangerous because they emit mostly UVA rays. Tanning beds emit “up to 15% times more UV radiation than the sun” (“Dangerous of Tanning”). Knowing that the sun bathing is not good, people go to the tanning salon. Many were convinced that indoor tanning is safer because it is controlled environment inside the bed. However this is not true because indoor tanning may “cause more damage than the sun’s standard UVU/UVB combination because UVA rays penetrate even deeper into the skin, causing lasting damage to important, fragile cells, include those in immune system”(Siddons). In 2009, a research...